The Neuropsychology Core (NC) will provide objective, standardized, and quantitative neuropsychological evaluations of patients and normal volunteers who sere as subjects in MADRC studies. These evaluations will serve as a basis for diagnostic accuracy and the development of operationally defined study variables and, thus, further our understanding of the pathophysiology of neurodegenerative disorders and dementia more generally. The NC will document changes in patient behavior over time, and coordinate the collection of neuropsychological data in projects and at satellite diagnostic and treatment centers (SDTCs) of the MADRC. This core will be responsible for training personnel at SDTCs and in specific projects that will be engaged in psychometric and other psychological applications and that are approved by the MADRC Executive Committee. The NC will participate in the selection of personnel for these projects, assignment of these personnel to functional units of the MADRC, and oversight of their ongoing activities once they are assigned. The NC will collaborate with NIH sponsored multicenter projects such as CERAD and ADCSU. The NC will provide consultation to existing projects and cores and assist in the development of future projects and center modifications. It will assist, when appropriate, in the design of projects, in their implementation, analyses, and communication of results. The NC will also provide the MADRC with expertise in behavioral measurement and behavioral principles in general, including normal conditions as well as psychopathological states. This will serve as a basis for training and consultation to other components of the MADRC, including MADRC sponsored conferences and the Community Outreach Education Program (COEP). In these endeavors, the NC will work collaboratively with the Clinical and Education and Information Transfer Cores as well as other projects of the MADRC.